Brown says Lockerbie bomber decision 'difficult'

But Gordon Brown gave no further indication of his views on the release of Abdelbaset Ali Al Megrahi on compassionate grounds.

A spokesman for the Prime Minister insisted: "It was and it remains a decision for the Scottish Justice Secretary."

The comments came as MSPs prepared to question Justice Secretary Kenny MacAskill in the Scottish Parliament later today.

The spokesman said: "Clearly the Prime Minister recognises this was a very difficult decision, and was clearly an extremely sensitive one, and there will be very strong feelings from the families of those people who were victims of this terrorist attack."

It was, he said, a "uniquely sensitive and difficult decision".

And asked whether the release gives succour to terrorists, the spokesman said: "I don't think it does.

"This was a decision taken by the Scottish Justice Secretary in accordance with the laws of Scotland. I don't see that anyone can argue that this gives succour."

Pressure has been increasing on Mr Brown to state his views on the release of Megrahi, jailed for life for the Lockerbie bombing but now dying from prostate cancer.

Liberal Democrat leader Nick Clegg said the Prime Minister's silence on Megrahi's release is "absurd and damaging".

Mr Clegg said: "Although the decision to release Megrahi was a Scottish one, for which Gordon Brown was not personally responsible, the fallout puts the UK at the centre of an international storm.

"In these circumstances it is absurd and damaging that the British Prime Minister simply remains silent in the hope that someone else will take the flak."

A former Labour First Minister of Scotland broke party ranks today to back the SNP minister's decision to release Megrahi.

Henry McLeish said the decision was "probably the right decision made for the right reasons", comments which made him the first senior Labour figure to back the decision publicly.

But another former Labour First Minister, Jack McConnell, who succeeded Mr McLeish, said Megrahi's release was "inexplicable".

Mr McLeish spoke out as Kenny MacAskill prepared to face his political opponents in the Scottish Parliament.

Today's special session of the Scottish Parliament, recalled a week early to discuss the issue, will hear a statement by Mr MacAskill, who will then be questioned.

Mr McLeish, who resigned in 2001, told BBC Radio Scotland's Good Morning Scotland programme: "If you look at the issue in the context of the criminal justice system and the independent legal system that we have, this is probably the right decision made for the right reasons."

He said he hoped the Scottish Parliament will focus on two issues – the process of taking the decision and the decision itself.

Mr McLeish also criticised the head of the FBI, Robert Mueller, who attacked the decision in a letter to Mr MacAskill.

He wrote: "The intervention of the director of the FBI was totally out of order.

"It would be the equivalent of the Metropolitan police chief writing to Barack Obama to complain about a decision."

He said Mr Mueller's criticism is "ill-informed", and added: "Quite frankly, it's none of his business.

"He has a view – fine.

"But that was a slur on the Scottish criminal justice system that we did not deserve."

There will be no vote following today's debate, and opposition politicians appeared to be in no hurry to table a no-confidence motion in Mr MacAskill – a move which, if it succeeded, may bring down the Government.

Scottish Labour justice spokesman Richard Baker told the programme: "Today is about asking questions of Kenny MacAskill.

"I have said before that he should resign on other issues, and this has been an act of unpardonable folly by the Scottish Government and by Mr MacAskill.

"But today is about showing the world that Kenny MacAskill did not speak for Scotland in making this decision."

Scottish Liberal Democrat chief whip Mike Rumbles said his party will seek a debate and vote on the decision when Parliament returns next week from the summer recess – "so that Scotland's position can be heard".

Mr Rumbles said: "We want Kenny MacAskill to listen to the debate we hopefully have next week and the vote, and that he does the decent thing".

Tory Bill Aitken said: "I think the question of resignations is at this stage premature."